coercion cic:/matita/excedence/eq_symmetric_.con.
-lemma eq_transitive: ∀E.transitive ? (eq E).
+lemma eq_transitive_: ∀E.transitive ? (eq E).
(* bug. intros k deve fare whd quanto basta *)
intros 6 (E x y z Exy Eyz); intro Axy; cases (ap_cotransitive ???y Axy);
[apply Exy|apply Eyz] assumption.
qed.
+lemma eq_transitive:∀E:apartness.∀x,y,z:E.x ≈ y → y ≈ z → x ≈ z ≝ eq_transitive_.
+
(* BUG: vedere se ricapita *)
lemma le_antisymmetric: ∀E.antisymmetric ? (le E) (eq ?).
intros 5 (E x y Lxy Lyx); intro H;
plus: carr → carr → carr;
zero: carr;
opp: carr → carr;
- plus_assoc: associative ? plus (eq carr);
- plus_comm: commutative ? plus (eq carr);
- zero_neutral: left_neutral ? plus zero;
- opp_inverse: left_inverse ? plus zero opp;
+ plus_assoc_: associative ? plus (eq carr);
+ plus_comm_: commutative ? plus (eq carr);
+ zero_neutral_: left_neutral ? plus zero;
+ opp_inverse_: left_inverse ? plus zero opp;
plus_strong_ext: ∀z.strong_ext ? (plus z)
}.
interpretation "Abelian group minus" 'minus a b =
(cic:/matita/groups/minus.con _ a b).
+lemma plus_assoc: ∀G:abelian_group.∀x,y,z:G.x+(y+z)≈x+y+z ≝ plus_assoc_.
+lemma plus_comm: ∀G:abelian_group.∀x,y:G.x+y≈y+x ≝ plus_comm_.
+lemma zero_neutral: ∀G:abelian_group.∀x:G.0+x≈x ≝ zero_neutral_.
+lemma opp_inverse: ∀G:abelian_group.∀x:G.-x+x≈0 ≝ opp_inverse_.
+
definition ext ≝ λA:apartness.λop:A→A. ∀x,y. x ≈ y → op x ≈ op y.
lemma strong_ext_to_ext: ∀A:apartness.∀op:A→A. strong_ext ? op → ext ? op.
assumption;
qed.
-coercion cic:/matita/groups/feq_plusl.con.
+coercion cic:/matita/groups/feq_plusl.con nocomposites.
lemma plus_strong_extr: ∀G:abelian_group.∀z:G.strong_ext ? (λx.x + z).
intros 5 (G z x y A); simplify in A;
assumption;
qed.
-coercion cic:/matita/groups/feq_plusr.con.
-
+coercion cic:/matita/groups/feq_plusr.con nocomposites.
+
+(* generation of coercions to make *_rew[lr] easier *)
+lemma feq_plusr_sym_: ∀G:abelian_group.∀x,y,z:G.z ≈ y → y+x ≈ z+x.
+compose feq_plusr with eq_symmetric_ (H); apply H; assumption;
+qed.
+coercion cic:/matita/groups/feq_plusr_sym_.con nocomposites.
+lemma feq_plusl_sym_: ∀G:abelian_group.∀x,y,z:G.z ≈ y → x+y ≈ x+z.
+compose feq_plusl with eq_symmetric_ (H); apply H; assumption;
+qed.
+coercion cic:/matita/groups/feq_plusl_sym_.con nocomposites.
+
lemma fap_plusl: ∀G:abelian_group.∀x,y,z:G. y # z → x+y # x+z.
intros (G x y z Ayz); apply (plus_strong_ext ? (-x));
apply (ap_rewl ??? ((-x + x) + y));
[1: apply plus_assoc;
|2: apply (ap_rewl ??? (0 + y));
[1: apply (feq_plusr ???? (opp_inverse ??));
- |2: apply (ap_rewl ???? (zero_neutral ? y)); apply (ap_rewr ??? (0 + z));
- [1: apply (feq_plusr ???? (opp_inverse ??));
- |2: apply (ap_rewr ???? (zero_neutral ??)); assumption;]]]]
+ |2: apply (ap_rewl ???? (zero_neutral ? y));
+ apply (ap_rewr ??? (0 + z) (opp_inverse ??));
+ apply (ap_rewr ???? (zero_neutral ??)); assumption;]]]
qed.
-
-
lemma fap_plusr: ∀G:abelian_group.∀x,y,z:G. y # z → y+x # z+x.
intros (G x y z Ayz); apply (plus_strong_extr ? (-x));
apply (ap_rewl ??? (y + (x + -x)));
[1: apply (eq_symmetric ??? (plus_assoc ????));
|2: apply (ap_rewr ??? (z + (x + -x)));
[1: apply (eq_symmetric ??? (plus_assoc ????));
- |2: apply (ap_rewl ??? (y + (-x+x)) (feq_plusl ???? (plus_comm ???)));
- apply (ap_rewl ??? (y + 0) (feq_plusl ???? (opp_inverse ??)));
+ |2: apply (ap_rewl ??? (y + (-x+x)) (plus_comm ? x (-x)));
+ apply (ap_rewl ??? (y + 0) (opp_inverse ??));
apply (ap_rewl ??? (0 + y) (plus_comm ???));
apply (ap_rewl ??? y (zero_neutral ??));
- apply (ap_rewr ??? (z + (-x+x)) (feq_plusl ???? (plus_comm ???)));
- apply (ap_rewr ??? (z + 0) (feq_plusl ???? (opp_inverse ??)));
+ apply (ap_rewr ??? (z + (-x+x)) (plus_comm ? x (-x)));
+ apply (ap_rewr ??? (z + 0) (opp_inverse ??));
apply (ap_rewr ??? (0 + z) (plus_comm ???));
apply (ap_rewr ??? z (zero_neutral ??));
assumption]]
theorem eq_opp_plus_plus_opp_opp:
∀G:abelian_group.∀x,y:G. -(x+y) ≈ -x + -y.
intros (G x y); apply (plus_cancr ??? (x+y));
-apply (eq_transitive ?? 0); [apply (opp_inverse ??)]
+apply (eq_transitive ?? 0 ? (opp_inverse ??));
apply (eq_transitive ?? (-x + -y + x + y)); [2: apply (eq_symmetric ??? (plus_assoc ????))]
apply (eq_transitive ?? (-y + -x + x + y)); [2: repeat apply feq_plusr; apply plus_comm]
apply (eq_transitive ?? (-y + (-x + x) + y)); [2: apply feq_plusr; apply plus_assoc;]
intros 5 (G x y z L);
apply (le_rewl ??? (0+x) (zero_neutral ??));
apply (le_rewl ??? (x+0) (plus_comm ???));
-apply (le_rewl ??? (x+(-z+z))); [apply feq_plusl;apply opp_inverse;]
-apply (le_rewl ??? (x+(z+ -z))); [apply feq_plusl;apply plus_comm;]
-apply (le_rewl ??? (x+z+ -z)); [apply eq_symmetric; apply plus_assoc;]
+apply (le_rewl ??? (x+(-z+z)) (opp_inverse ??));
+apply (le_rewl ??? (x+(z+ -z)) (plus_comm ??z));
+apply (le_rewl ??? (x+z+ -z) (plus_assoc ????));
apply (le_rewr ??? (0+y) (zero_neutral ??));
apply (le_rewr ??? (y+0) (plus_comm ???));
-apply (le_rewr ??? (y+(-z+z))); [apply feq_plusl;apply opp_inverse;]
-apply (le_rewr ??? (y+(z+ -z))); [apply feq_plusl;apply plus_comm;]
-apply (le_rewr ??? (y+z+ -z)); [apply eq_symmetric; apply plus_assoc;]
-apply (fle_plusr ??? (-z));
-assumption;
+apply (le_rewr ??? (y+(-z+z)) (opp_inverse ??));
+apply (le_rewr ??? (y+(z+ -z)) (plus_comm ??z));
+apply (le_rewr ??? (y+z+ -z) (plus_assoc ????));
+apply (fle_plusr ??? (-z) L);
qed.
lemma fle_plusl: ∀G:ogroup. ∀f,g,h:G. f≤g → h+f≤h+g.
intros (G f g h);
apply (plus_cancr_le ??? (-h));
-apply (le_rewl ??? (f+h+ -h)); [apply feq_plusr;apply plus_comm;]
+apply (le_rewl ??? (f+h+ -h) (plus_comm ? f h));
apply (le_rewl ??? (f+(h+ -h)) (plus_assoc ????));
-apply (le_rewl ??? (f+(-h+h))); [apply feq_plusl;apply plus_comm;]
-apply (le_rewl ??? (f+0)); [apply feq_plusl; apply eq_symmetric; apply opp_inverse]
+apply (le_rewl ??? (f+(-h+h)) (plus_comm ? h (-h)));
+apply (le_rewl ??? (f+0) (opp_inverse ??));
apply (le_rewl ??? (0+f) (plus_comm ???));
-apply (le_rewl ??? (f) (eq_symmetric ??? (zero_neutral ??)));
-apply (le_rewr ??? (g+h+ -h)); [apply feq_plusr;apply plus_comm;]
+apply (le_rewl ??? (f) (zero_neutral ??));
+apply (le_rewr ??? (g+h+ -h) (plus_comm ? h ?));
apply (le_rewr ??? (g+(h+ -h)) (plus_assoc ????));
-apply (le_rewr ??? (g+(-h+h))); [apply feq_plusl;apply plus_comm;]
-apply (le_rewr ??? (g+0)); [apply feq_plusl; apply eq_symmetric; apply opp_inverse]
+apply (le_rewr ??? (g+(-h+h)) (plus_comm ??h));
+apply (le_rewr ??? (g+0) (opp_inverse ??));
apply (le_rewr ??? (0+g) (plus_comm ???));
-apply (le_rewr ??? (g) (eq_symmetric ??? (zero_neutral ??)));
-assumption;
+apply (le_rewr ??? (g) (zero_neutral ??) H);
qed.
lemma plus_cancl_le:
∀G:ogroup.∀x,y,z:G.z+x ≤ z+y → x ≤ y.
intros 5 (G x y z L);
apply (le_rewl ??? (0+x) (zero_neutral ??));
-apply (le_rewl ??? ((-z+z)+x)); [apply feq_plusr;apply opp_inverse;]
+apply (le_rewl ??? ((-z+z)+x) (opp_inverse ??));
apply (le_rewl ??? (-z+(z+x)) (plus_assoc ????));
apply (le_rewr ??? (0+y) (zero_neutral ??));
-apply (le_rewr ??? ((-z+z)+y)); [apply feq_plusr;apply opp_inverse;]
+apply (le_rewr ??? ((-z+z)+y) (opp_inverse ??));
apply (le_rewr ??? (-z+(z+y)) (plus_assoc ????));
-apply (fle_plusl ??? (-z));
-assumption;
+apply (fle_plusl ??? (-z) L);
qed.
lemma le_zero_x_to_le_opp_x_zero:
∀G:ogroup.∀x:G.0 ≤ x → -x ≤ 0.
intros (G x Px); apply (plus_cancr_le ??? x);
-apply (le_rewl ??? 0 (eq_symmetric ??? (opp_inverse ??)));
-apply (le_rewr ??? x (eq_symmetric ??? (zero_neutral ??)));
-assumption;
+apply (le_rewl ??? 0 (opp_inverse ??));
+apply (le_rewr ??? x (zero_neutral ??) Px);
qed.
lemma le_x_zero_to_le_zero_opp_x:
∀G:ogroup.∀x:G. x ≤ 0 → 0 ≤ -x.
intros (G x Lx0); apply (plus_cancr_le ??? x);
-apply (le_rewr ??? 0 (eq_symmetric ??? (opp_inverse ??)));
-apply (le_rewl ??? x (eq_symmetric ??? (zero_neutral ??)));
+apply (le_rewr ??? 0 (opp_inverse ??));
+apply (le_rewl ??? x (zero_neutral ??));
assumption;
qed.